(i) Technical Field
The present invention relates to an image processing apparatus, a non-transitory computer readable medium, and an image processing method.
(ii) Related Art
Deterioration caused by the color boundary may be generated in images. For example, in images read out by an image reading apparatus, colors which do not exist in an original image may be generated in the color boundary due to the reading error. In addition, when restoration is performed on images which are encoded or compressed using a encoding system or a compression system in which methods of performing frequency transforms such as a discrete cosine transform or a discrete Fourier transform for each block and performing quantization are used, a block noise called, for example, a mosquito noise or the like may be generated. Further, a change in the color or the concentration is performed intentionally on the color boundary, for example, in enhancement filtering, but in images which are excessively corrected due to this process, a referrer may feel that deterioration is generated in the color boundary portion.
On the other hand, there is a smoothing process as a technique for removing the noise component or the difference in the color. The smoothing process is basically performed by calculating an average value of the colors in the pixel range having a predetermined size.